"The important thing is not to concede. We don't have much experience (of that) so it's important that we start off well defensively."

Chelsea represent England's last realistic hope of having a team in the Champions League quarter finals with City and United falling at the group stage and Arsenal virtually out having been thumped 4-0 in their first leg against Milan.

But Mazzarri, whose side eliminated City in the group stages, believes the big difference is Italian sides are improving rather than the English getting worse.

"Arsenal are in a construction phase but it is Italian football that has changed rather than English football," said Mazzarri.

"There won't be much tactical difference between Chelsea and City.

"For me preparing for Chelsea is like preparing for Chievo. I've been used to preparing ever more important matches for many years because I started at the bottom.

"Tactically Cheslea have recently used 4-4-2 as well as 4-3-3, we've tried to study them well."